Cutting-nippers.



S. BUTTERWORTH.

.CUTTING NIPPERS.

APPLICATION FILED DEC-31,1917.

Patented Sept. 17,1918.

R m E V N ms Nakms rncns co PnaTD-urum. WASNINOWN. o. c.

SAMUEL BUTTERWOR'IH, or EVERETT, MASSACHUSETTS.

CUTTING-NIPPERS.

Specification of Letters Patent.

Patented Sept. 17, 1918.

Application filed December 31, 1917. Serial No; 209,743.

To all whom it may concern:

Be it known that I, SAMUEL BUTTER- wonTH, a citizen of the United States, residing at Everett, in the county of Middlesex and State of Massachusetts, have invented new and useful Improvements in Cutting- Nippers, of which the following is a specification.

This invention relates to cutting nippers comprisinga pair of levers fulcrumed on a supporting body, each lever having a longer and a shorter arm and a pair of cutters detachably secured to the shorter arms, the nippers also including operating levers fulcrumed on the body and having shorter arms engaging the longer arms of the cuttercarrying levers, and longer arms adapted to be manipulated to cause the cutters to forcibly approach each other. Y

The. invention has for its object to pro vide certain improvements relating to the shorter arms of the cutter-carrying levers, and to the form of the cutters, whereby strains exerted on the cutters, tending to displace the same from their operative positions, are resisted entirely by the said shorter arms and cutters, so that the relatively small screws employed to secure the cutters to the levers are entirely relieved from the duty of resisting said strains.

The invention is embodied in the improvements which I will now proceed to describe and claim.

Of the accompanying drawings forming a part of this specification,

Figure 1 is a side elevation of a pair of cutting nippers embodying the invention.

Fig. 2 is a perspective view of one of the cutter-carrying levers, without the cutter.

Fig. 3 is an edge view of said lever.

Fig. 41 is a perspective view of one of the cutters.

Fig. 5 is a section on line 55 of Fig. 1.

Fig. 6 is a section on line 66 of Fig. 1.

The same reference characters indicate the same parts in all of the figures.

The body of the nippers includes a pair of parallel plates 12, these plates belng connected by transverse screws 13 and 14, the screws 13 constituting the fulcrums of the cutter-carrying levers, while the screws 14= constitute the fulcrums of the operating levers hereinafter described.

Each cutter-carrying lever 15 includes a longer arm 15 and a shorter arm 15*, these being formed in one piece which is provided with an orifice 17 to receive a fulcrum screw 13. The shorter arm 15 is enlarged to form a transverse head 18. Said head is 'provided with a V-shaped cutter-receiving recess having two faces 19 and 20 which meet at an acute angle. The face 19 forms a side rest and the face 20 a back rest for a cutter 21. Said cutter is preferably substantially rhomboidal in cross section, and has a flat inner side 22, formed to bear on the side rest 19, a cutting edge'23, a beveled back 24 formed to be seated on the back rest 20, and a flat outer side 25 parallel with the inner side 22. The cutting edge 23 is formed by the intersection of the outer side'25 with the outer edge face 26 of the cutter.

The head 18 is provided with tapped orifices 27, and the cutter is provided with orifices 28 coinciding with the orifices 27, said orifices being adapted to receive the shanks of attaching screws 29, the heads of which bear on the outer sides of the cutters.

It will be seen by reference to Fig. 1, that the inner sides 22 and beveled backs 24 of the cutters bear respectively on the side rests 19 and back rests 20 of the cuttercarrying levers, the arrangement being such that the back rests 20 cooperate with the beveled backs 24 in resisting strains tending to separate the cutters from the side rests 19. The screws 29 are therefore relieved of the duty of resisting such strains, the function of the screws being simply to confine the cutters in place when the instrument is not in use. When the cutting edges are pressed simultaneously against an interposed body to be cut, the strain or pressure exerted on the cutters holds them against the rests 19 and 20 the same as if the screws 29 were not present, the only function of the screws being to prevent the cutters from dropping away from said rests when the cutters are not in action.

It will be seen that a cutter formed to fit the rests 19 and 20 is of extremely simple form, so that a workman desiring to replace a broken cutter can improvise a new cutter from a strip of steel, using appliances readily accessible in any machine shop.

Referring to Figs. 5 and 6, it will be seen that the plates 12 are spaced apart by two pairs of tubular struts, namely, two struts 30 which may be called a pair of outer struts, and two struts 31 which may be called a pair of inner struts. The inner sides of the plates are countersunk to receive the ends of the struts, and the screws 13 and 14 pass through the plates and the struts, said screws being threaded only at one end portion and engaged with tapped orifices in one of the plates 12, as clearly shown by Figs. 5 and6.

The operating levers 32 are fulcrumed on the inner struts 31 and have shorter arms engaging the longer arms of the cutter-carrymg levers, said longer arms being adapted to be manipulated by the operator.

The struts 30 and 31 maintain the plates 12 suitably spaced apart and prevent the plates from binding on the interposed portions of the levers when the screws 13 and 14 are tightened.

. The countersinks in the plates 12 and the ends of the struts projecting into said countersinks contribute materially to the strength of the device. To compensate for the countersinking of the plate 12 having the tapped orifices engaging the screws 13 and 14, I offset the said plate as shown'at 12.

I claim:

1. Cutting nippers comprising a body, a pair of cutter-carrying levers fulcrumed on the body, each lever having a longer and a shorter arm and a transverse head on the shorter arm provided with a V-shaped cutterreceiving recess, the faces of which meet at an acute angle, one of said faces forming a side rest, while the other face forms a back rest, a pair of cutters each having a cutting edge, a fiat inner side seated on said side applying force to the cutter-carrying levers.

2. Cutting nippers comprising a body composed of parallel plates, a pair of tubular outer struts and a pair of tubular inner struts interposed between said plates, the plates being countersunk to receive the ends of the struts, and headed screws passing through said plates and struts and engaging tapped orifices in one of the plates, a pair of cutter-carrying levers fulcrumed on the' outer struts each lever having a longer and a shorter arm, cutters secured to the shorter arms of said levers, and a pair of operating levers fulcrumed on the inner struts and having shorter arms engaging the longer arms of the cutter-carrying levers, said struts constituting fulcrums for said levers and spacing members maintaining said plates suitablyspaced apart.

In testimony whereof I have aflixed my signature.

SAMUEL BUTTERWORTH.

Gopieso! this patent may be obtained for five cents each, by addressing the Commissioner of Batents. Washington, D. 0." 

